Check out these activities that explore sound transmission inspired by the 4-H website.
Sounds can be loud like a train going by or quiet like leaves rustling in a light breeze. But sounds can also be high like a tea pot whistle or low like a fog horn. The loudness or quietness of a sound is its volume. The highness or lowness of a sound is its pitch. In this activity, you’ll make a stringed instrument and see what it takes to switch the pitch!
• Ruler with holes
• Rubber band
• Paper cup
• Masking tape
• Thumb tack
1. Use the point of a thumb tack to poke a small hole in the center of the bottom of the cup.
2. Cut a rubber band and push one end through the hole from the outside of the cup.
3. Tie 2 or 3 knots in the rubber band so that it will not pull out of the hole when stretched.
4. Put the other end of the rubber band through a hole near the end of the ruler. Tie the rubber band so that it is securely attached to the ruler.
5. Pull the cup to the other end of the ruler so that the rubber band is stretched but not too tight. Use masking tape to tape the cup to the ruler as shown.
6. Hold the cup near your ear and use your thumb and index fingers to pinch the rubber band. Then have a partner pluck the rubber band. Move your hand a short distance up the rubber band toward the cup and pinch the rubber band again while having your partner pluck the rubber band again. Did the pitch of the sound change? Did it seem higher or lower?
7. Move your hand further toward the cup again, pinch, and have your partner pluck the rubber band again. How did the pitch change this time? Pinch the rubber band closer and further from the cup and have your partner pluck it each time to hear the switch in pitch!
Think about this:
You can try another activity to see if you can change the pitch of a vibrating piece of wood or plastic:
1. Lay a ruler on a table so that about 2/3 of the ruler is off the table.
2. Have a partner use one hand to firmly hold the ruler down on the table while you give the other end a little hit with your index finger. Listen closely to the sound.
3. Have your partner pull the ruler back a little so that the part sticking off the table is a bit shorter. Make sure your partner is holding the ruler down and then flick it with your finger again and listen to the sound. Is the pitch higher or lower than before?
4. Repeat step 3 a few more times.
5. What did you notice about how the pitch was related to the length of the vibrating part of the ruler?
Where’s the Chemistry?
The pitch of a sound made by a string depends on how fast the string vibrates. The number of vibrations in a period of time, like a second, is called the frequency of the vibration. The frequency at which a string vibrates depends on the material the string is made of, how tight the string is stretched, and the length of the string. As you move your fingers up the rubber band and pinch it between your fingers, you are shortening the length of rubber band that can vibrate. The shorter the length of rubber band that can vibrate, the higher the sound; the longer the length of rubber band that can vibrate, the lower the sound.
Materials (per child):
- 6-inch cardboard tube (toilet tissue or paper towel)
- wax paper (enough to cover one end of the tube)
- a rubber band
- crayons or markers for decorating.
You will need to make a hole in each child’s tube as shown. Invite the children to join you at the tables. Ask the children if they know how to hum. Have them practice humming for a minute. Tell them that a kazoo is an instrument that helps make a humming sound louder by making more vibrations. Have the children place the wax paper over one end of the tube. Hold the wax paper in place by putting the rubber band around the tube as shown. Ask the children to hum into the open end of the kazoo. Choose a tune that all of the children know (for example: “ABC’s” or “Happy Birthday” if someone’s birthday is near). Have the group form a kazoo band and “play” a song as a group. Ask the children the following questions: Does your humming noise sound different when you use a kazoo? What is vibrating on your kazoo? Do you think that changing the length of the kazoo would change the sound? Try it. How do you think a larger kazoo would sound? The tube a carpet comes rolled on would show how the same sound waves spread out in a larger space make a lower sound. Application: All musical instruments use vibrations to make sound. What is vibrating in a piano? (strings struck by the small hammers in the piano) A clarinet? (the reed or mouthpiece) A drum? (the skin) A guitar? (strings)
GIVE ME A S-O-U-N-D RAH… RAH…. RAH…..
A megaphone is another great way to study sound and how we can direct it to different areas and adjust the amount of sound waves that reach our ears.
- clear tape
- one sheet of construction paper (9 x 12 inches or larger) for each child
- markers or crayons for decorating,
- scissors (optional)
Explain to the children that sound waves travel out in all directions, but we can make those sounds travel in a certain direction by making a mega-phone. Help the children to shape the construction paper into a cone with a large hole at one end and a small hole (about 1 /2 inch in diameter). Hold the cone in place with tape. If you wish, cut the ends of the cone to make them even. Let the children decorate the outside of their megaphones. Try them out! Ask the children: What does it sound like when someone talks
through the megaphone? How is it different than when someone talks without the megaphone?
What does it sound like when they point the megaphone away from you when they talk?
Why do you think this happens? (Explain that the megaphone only allows the sound to travel out in the direction of the hole in the cone.)
Application: Sometimes cheerleaders use megaphones at sporting events. When are some other times that you would want to direct sound in a certain direction? (Whispering in someone’s ear, calling someone to come in from outside, when someone wants to listen to the radio but others don’t want to hear it)
How would you direct the sound? (cupping hands, using earphones)
Find a fun way to study sound vibrations with this quacky activity.
- bowl filled with water per child
- a plastic cup (bathroom or 8 ounce size), 18 inch
- cotton string,
- a paper clip
You will need to poke a hole with scissors or a nail and hammer (big enough for the string to fit through) in the bottom of each plastic cup prior to the activity. Have the children tie one end of the string to the
paper clip. (This may be done ahead of time for younger children, or it could be an opportunity for learning how to tie.) Thread the other end of the string through the inside of the cup and pull the string down until the paper clip rests on the bottom of the cup. The children should dip the string in the bowl of water and get their fingers wet. Have them pull their fingers down the string. (It should make a loud noise. If it doesn’t work well, make sure their string is wet.)
If time allows, let the children experiment with different sizes and types of cups and different types and lengths of string. What type of cup makes the loudest noise? The quietest? Does the type or length of
string affect the sound your cup makes? How? Ask the children the following questions: What happens when you pull your fingers down the string? What causes the loud noise? (Your fingers create friction on the wet string which vibrates in the cup and creates a sound.)
What does the “quacky” cup sound like?
How could you change your cup to make a different sound?
How are a guitar and a violin like the instrument you just made?
What other musical instruments use strings to make sounds? (banjo, fiddle, harp, cello, piano)
COOKING UP SOME SOUNDS
Perfect STEM ON A SHOESTRING activity to study sound & vibrations!
- kitchen gadgets: metal, wooden, and plastic (for example: large metal spoons, whisks, wooden spoons, baking racks, spatulas, tongs, measuring cups);
- pencils (one for each pair of children)
Cut the string into 2-foot lengths. Tie a gadget in the center of each piece of string. Ask the youth if the kitchen gadgets you have in front of you make sounds. What types of sounds do you think they make? We are going to listen to sounds in a fun and different way. Demonstrate how to listen to the kitchen gadgets. Wrap the ends of the string around your index finger several times. Hold it in place with your thumb. Hold your fingers up to your ears as if plugging them. Ask one of the children to strike the gadget with a pencil. Explain the sound you hear to the group. Have the children work in pairs to test the different items. Encourage them to try all the gadgets and to talk with their partner about what they are hearing.
Ask the children the following questions:
- How were the sounds alike?
- How were they different?
- Why do you think you can hear sounds through the string? (Sounds travel better through solids than through the air. The string vibrates and causes the sound to travel to the ear.)
Ask the children to categorize the kitchen gadgets in different ways. Let them discuss the categories that they used. What were their favorite and least favorite gadgets for making sounds?
Rubber Band Guitar
Make your very own guitar out of an empty shoe box and rubber bands and strum away! Studying sound while having a little FUN!!!
• 1 tissue box
• 1 ruler or popsicle stick
• Rubber bands
1. Remove all plastic from the empty tissue box.
2. Stretch as many rubber bands around the box as you would like.
3. Tape the ruler or craft stick to the back of the tissue box (the side without the hole) to be the arm of the guitar. Insert a crayon under one end of rubber bands on box.
4. Play your guitar by strumming and plucking the rubber bands that cover the hole.
Here is the finished product that is an excellent study of sound and tension.
SHAKE SHAKE SHAKE … SHAKE YOUR EGG SHELL
Study sound and sound direction by shaking up your plastic eggs with some organic fillings.
o plastic Easter eggs
o filling – rice and barley are recommended, but you can also fill different eggs with different things and have children compare sounds
o hot glue gun, and hot glue
Put a couple of tablespoons (you can experiment with sound before sealing) of rice or other filling in bottom half of egg. Run a bead of hot glue along the inside edge of the TOP of the egg. Carefully place top on and check to be sure it’s on straight and tight.
The larger size egg is fun, but if you use eggs the size of real eggs, you can store them in egg cartons painted to match the egg colors and children can sort them when putting them away.
JINGLE ALL THE WAY
Make jingle sticks to help students study different sounds that happen in the environment.
o six metal bottle caps for each stick
o six inch dowels or sticks
o common nails, approx. 1 3/4″ long
o one nail larger in diameter, to use to punch holes in bottle caps
o Polyurethane or other clear finish
o optional: different colored electrical tape, and permanent black marker
Coat dowels with 2 coats of polyurethane, and allow to dry. Using larger nail, hammer holes in the centers of the bottle caps. Using common nails, hammer 3 sets of 2 bottle caps each along one side of the dowel, leaving enough dowel for handle. If desired, decorate handle end of dowel with bands of electrical tape, and draw design on tape with maker